This invention is an improvement over the keyboard shown in U.S. Pat. Nos. 3,860,771, or 3,721,778, and others in which pins or a portion of a circuit extend from the top to the bottom of a support in order to make connections between circuit patterns above and below the support.
In this invention the contactor supporting sheet is provided with protrusions or domes which support portions of a circuit pattern. The protrusions are continuously urged by the keyboard frame, adhesive, or both into contact with an underlying circuit pattern.
Applicant would like to cite the following U.S. Pat. Nos.: 3,383,487; 3,991,463; 3,818,279; 3,861,135; 3,680,037; 3,469,016; 3,437,529; 3,557,446; and Great Britain Pat. No. 940,518.